Presser foot for sewing machines



' June 2-4, 1930. M FA T 1,765,604

PESSER FOOT FOR SEWING MACHINES Filed April so, 1928 Patented June 24, 1930 UNITED "STATES PATENT oFFicE JAMES R. MOFFATT, OF CHICAGO, ILLINOIS, ASSIGNOR T0 UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF IIILINOIS PRESSER FOOT FOR SEWING MACHINES Application filed April 30, 1928.

The invention relates to new and useful improvements in presser feet for sewing machines, and more particularly to a presser foot which is adapted to be used in stitching fabrics with a stitching mechanism which forms covering stitches.

It is a common expedient to provide a stitching mechanism for forming covering stitches that are joined above and below to cover the fabric, and to provide such a stitching mechanism with fingers over which the cross thread loops are laid.

An object of the present invention is to provide means for supporting the stitch lingers over which the cross thread loops are formed so that the fingers may remain close to the fabric being stitched when the presser foot is raised by a cross seam or the like passing from beneath the foot, and thus prevent the fabric from drum heading, that is, moving up and down with the needles.

A further object of the invention is to provide a presser foot of the above type having means for turning down the upper section of fabric in overlapped relation to the lower section of fabric, which turning down means supports the stitch fingers and moves up and down therewith.

These and other objects will in part be obvious and will in part be hereinafter more fully disclosed. I

In the drawings which show by way of illustration one embodiment of the inventio-n:

Figure 1 is a top plan view of a presser foot embodying the improvements;

Fig. 2 is a bottom plan view of the same;

Fig. 3 is a side view of the finger over which the cross thread loops are laid, and the supportingmeans therefor Fig. 4 is a sectional view on the line 44 of Fig. 3; p

Fig. 5 is a perspective view of the support and stitch fingers carried thereby;

Fig. 6 is a view showing more or less diagrammatically thepresser foot in side elevation with parts broken away and showing the foot raised by the cross seam and the stitch fin erlowered so as to hold the fabric a from drum heading Serial No. 274,117.

Fig. 7 is a view similar to Fig. 8, but showing the cross seam as having passed beneath the member which lifts the stitch fingers, and prepares the concatenated thread loops to raise the cross seam;

Fig. 8 is a section on the line 88 of Fig. 2 and showing the fabric held down by the yielding turning down portion when the foot is slightly raised.

The invention is directed to a presser foot for sewing machines of the type wherein a fabric is stitched by a covering stitching mechanism. The covering mechanism includes two or more needles with which a single looper cooperates, so as to join the needle thread loops beneath the fabric, and with which a cover thread laying mechanism cooperates for forming cross thread loops which are secured by the needle threads above the fabric. Such a stitching mechanism covers the fabric between the extreme needles. This covering stitching mechanism is particularly useful in connection with the stitching of knit goods, where it is desired to cover and conceal raw edges of material. It is also a common expedient to use in conjunction with such a stitch forming mechanism, stitch fingers, both on the throat plate and on the presser foot, which stitch finger on the presser foot is disposed so that it lies between the extreme outer needles, and the cross thread loops are laid over the finger and drawn down against the finger, and finally fed off from the end of the stitch finger. This makes more or less of an elastic seam, and also a seam where the stitches may be drawn reasonably tight without puckering or distorting the seam. Often in stitching fabric sections, a cross seam passes beneath the presser foot. This cross seam often includes an elastic tape loading at ri ht an les to the seam .bein stitched.

the fabric down on the presser foot in the machines as heretofore designed.

The present invention has to do with the mounting of the stitch fingers so that they may remain close to the fabric being stitched, even when the presser foot is raised in the manner stated. This is accomplished, by providing a supporting member which is pivoted to the presser foot well in rear of the needle opening therethrough, and this supporting member carries the stitch fingers. It is spring-pressed downward, and means is provided for limiting its downward movement. \Vhen the presser foot is bodily raised by the passing of a cross seam beneath the same, the support for the stitch fingers will be lowered at' the end thereof where the fingers are mounted, and this will cause the fingers to remain close to the fabric. The portion of the foot, carrying the stitch fingers also turns down the top section of the fabric and this also moves and remains in operating engagement with the fabric when the foot is slightly raised.

Referring more in detail to the drawings, the invention is shown applied to a presser foot which includes a body portion 1 carried by a shank 2. This presser foot is provided with a needle opening 3 through which the needles pass in the stitching of a fabric. The presser foot is also provided with a guiding channel t, as it is especially adapted for use in conjunction with the stitching of overlapped edge portions of fabric sections. The edge portions are raised and fed into this guiding channel in substantially vertical position. A finger5 extends lengthwise of the guiding channel 4 and divides this channel into two separate channels, one for each edge portion of the fabric sections which are being joined. The channel at the left of this finger 5 terminates in a recess formed in the supporting shank 6 of the finger, and this recess is so shaped as to turn down the edge, portion passing along this channel.

The channel on the other side of the finger 5 terminates in a recess, the rear wall of which is formed by a member 7 which carries the stitch fingers 8, 8. This recess is so shaped that the fabric sections passing along the channel at the right of the finger 5 are turned down flat on to the first-named portion. The trimming devices 9, 9 are provided for trimming the fabric sections while in raised position. The presser foot referred to above in detail,.is shown, described and claimed in my co-pending application Serial No, 248, l56, filed January 21, 1928. The needles of the stitch forming mechanism are indicated atlO, 10. The cross thread laying.

mechanism'and the loeper mechanism have not been shown. 7

The stitch fingers 8, 8 are carried by the member7 as noted and this member 7 V is side of this member 7 is arched and curved so as to turn down the top edge portion of the fabric section into fiat overlapping relation onto the lower section of fabric. The presser foot is provided with a recess 15' in the side wall of the channel which receives the upturned edge portions of the fabric section, and this member 7 has a depending portion 15 which lies in this recess. The depending portion 15 is fiat on its under face and when the presser foot rests flatly on the fabric section then this flat lower face of the member 15 will also rest on the fabric section.

At this time the stitch fingers are properly i positioned relative to the fabric section so that the stitches may be formed over the same and fed off from the ends thereof in the usual manner. i The arm 11 is yieldingly pressed downwardly by a spring 13 attached to a holding screw 14 and bearing against the upper face of the arm 11. In Figs. 6, 7, and 8 I have shown more or less diagrammatically a fabric F in which has been formed a pocket containing an elastic strip The work support is indicated at 17 in these figures. As the fabric passes underneath the presser foot this cross pocket with the elastic tape f therein will raise the presser foot as shown in Fig. 6. As the presser foot moves up the supporting arm 11 will be depressed by its spring and this will move the member 7 downward holding the stitch finger 8 down against the fabric section. This prevents the fabric from drum heading during the reciprocation of the needles. Such a structure is particularly useful in stitching rayon silk which is very thin and in the formation of garments which have elastic tapes extending across the path of the line of stitching. The pres'sor foot is raised toa considerable extent from the fabric. The stitch fingers remain in proper position for the formation of stitches over the same and thus the fabric is properly 8 held down during this stitching period when the presser foot is raised. After the cross seam has passed from beneath the presser footthen the presser foot will move down onto the fabric sections. This, of course, causes the stitch fingers to be raised to position flush with the lower face of the presser foot. The member 15 extends beneath the presser foot when it is raised in the manner statedand will move up with the stitch fingers to a position where the lower edge thereof is flush with the bottom of the foot. This maintains the recess in which the member 15 slides closed and prevents the garment from catching on any sharp edge of the foot at any time during the stitching of the same.

Furthermore, the section of the foot which turns down the upper layer of the fabric sections carries the stitch fingers and moves up and down therewith. Therefore, when the presser foot is raised and the fingers drop to maintain contact with the fabric as it is stitched during the passing of the elastic tape the portion of the foot which turns down the upper section likewise remains in contact with the material, although the presser foot is raised. The depending portion 15 lies close to the wall of the channel 4 and will prevent any lateral or outward swing of the support 11. A post 18 threaded into the foot portion of the presser foot has the face thereof adjacent the support 11 flattened. This serves to prevent any lateral swing of the support 11 to the left as viewed in Figure 1.

It is obvious that minor changes in the details of construction and the arrangement of parts may be made without departing from the spirit of the invention as set forth in the appended claims.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A presser foot for sewing machines including in combination a body portion havinga needle opening therethrough, a guiding channel extending from the front end of the foot portion longitudinally thereof for directing upturned edge portions of the fabric sections, said presser foot having means for turning down said edge portions into overlapped relation with each other, said presser foot at the inner end of the channel and in front of the needle opening having a vertically movable section carrying the turning down means for the top section, and means for yieldingly supporting the same whereby said movable section moves downward and remains in contact with the fabric section when the presser foot is raised by the passing of a cross seam beneath the' same.

2. A presser foot for sewing machines including in combination a body portion having a needle opening therethrough, a guiding channel extending from the front end of the foot portion longitudinally thereof for directing upturned edge portions of the fabric sections, said presser foot having means for turning down said edge portions into over lapped relation with each other, said presser foot having at the inner end of the channel and in front of the needle opening a vertically movable section carrying the turning down means for the top section, means for yieldingly supporting the same whereby said movable section moves downward and remains in contact with the fabric section when the presser foot is raised by the passing of a cross seam beneath the same, and a stitch finger carried by said movable section.

8. A presser foot for sewing machines including in combination a body portion having a needle opening there-through a guiding channel extending from the front end of he foot portion longitudinally thereof for directing upturned edge portions of the fab ric sections, said presser foot at the inner end of said channel and in front of said needle opening having a vertically movable section adapted to engage and turn down the upper fabric section-in overlapped rela tion on the lower fabric section, means for yieldingly supporting said movable section, stitch fingers carried by said movable section and extending into the needle opening and adapted to move beneath the surface of the presser foot when said presser foot is raised.

4. A presser foot for sewing machines including in combination a body portion having a needle opening therethrough, a guiding channel extending from the front end of the foot portion longitudinally thereof for directing upturned edge portions of thefabric sections, said presser footat the inner end of said channel having a vertically movable section adapted to engage and turn down the upper fabric section in overlapped relation on the lower fabric section, means for yieldingly supporting said movable section, stitch fingers carried by said movable section and extending into the needle opening and adapted to move beneath the surface of the presser foot when said presser foot is raised, said presser foot having a guiding recess in the wall of said channel and said movable section having a member adapted to engage said recess, said member being flush with the side wall of the channel and with the bottom of the presser foot when raised.

5. A presser foot for sewing machines including a body portion having a needle opening therethrough, a stitch finger located in said opening and mounted for movement therein, means adapted to urge said stitch finger in one direction, and devices connected to said stitch finger and located wholly in advance thereof adapted to contact the fabric passing under said presser foot and by said contact to determine the vertical position of said finger relative to the presser foot.

In testimony whereof, I affix my signature.

JAMES R. MOFFATT. 

